As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
STRG. 20R BETWEEN FS 310.00 TO FS 349.00 FOUND TO BE CORRODED UPON REMOVAL OF THE AFT INTERCOSTAL. (C-CHECK) RO 4/21/2020 REMOVED AND REPLACED STRINGER 20R, FS319-7 - FS349. REF CRJ-200 SRM AND BOMBARDIER DWG. SEE CONTINUATION CARD FOR DETAILS.